Boomerangs: Magic Sticks of Physics

net a full beard. No, without he took away the beard would be like any number of my friends from elementary school. Yeah. There was always that one guy though that had the early early facial hair. My you know, jimsa Middle Eastern. He sort of had a little mustache in like the seventh grade. I had a friend named ron in Uh in elementary school. Man. He had like a deep voice and like the mustache and everything. It may have been fourth or fifth grade. Now he sells

steer is. Yeah, so obviously we're talking boomerangs, Chuck, that's right, And um, if you associate boomerangs with Australia, there's actually a pretty good reason for that. It turns out the boomerangs, what do you think of a boomerang, which is kind of like a crescent shaped stick that you throw and it just comes back to you eventually and you catch it and look at your friends and say pretty cool.

Huh yeah there, Like how do you do that? That was most people think perfected in um by aborigines in Australia. That's right. If you want to go back even further, UM, well, there's a couple of types of boomerangs. Well, there's many types of boomerangs, but two main categories is one that returns to you that you play with, and the one that you go out and try and kill animals with that does not return to you. UM. I call those the sad boomerangs. Some people call him rabbit sticks rabbit

Oh no, I know, isn't that mean? But if you want to learn how to make one yourself, go to um Survival Skills, the website the Hunting Boomerang. It's actually it's pretty cool. This guy does. He makes he's he shows you step by step how to make a boomerang natural skills, I'm sorry skill. He just goes out in the woods and finds like a kind of roughly boomerang shape stick and then use it into like a functioning, non returning boomerang is pretty awesome. Well, and that's what

people theorize is how the boomerang came about. Um Back in Took Took's day, they would eventually learn to take a club and beat an animal on the head. And then maybe one of Took Took's rand was smart enough to say, Hey, maybe if I throw this at the animal from a distance, I won't scare them away, or that animals faster than I can run, But I can throw a stick faster than the animal can run. Let me hit it in the head with the stick. That's right.

And so over time, just like with any early tool um evolution, I guess you would uh find sticks that flew better and further and further, and eventually they sort of took the shape of a boomerang because of its unique flying properties. Yeah, they figured out that like a curved stick, well, you can aim it more easily and it'll fly longer. So they started selecting for those kind of sticks, and then they started making those sticks themselves,

like somebody from the Natural Skills website would. Yeah, the two the the design of the two different branches made it more stable. Yeah, and we'll get into the mind bending physics behind a boomerang. Boomerangs, frankly, are magic sticks of physics. They're almost they're almost it's almost impossible to understand them, like what's going on? But we're gonna do our best to explain it. And it's with a non

returning boomerang. It's kind of straightforward. It's the returning boomerang that they say the Aboriginal Australians were the first to invent. That is really difficult to grasp the physics behind. Yeah, and the oldest non returning boomerang they found in Poland from about twenty years ago. Yeah, that's surprising to me. And what that was that far ago? Know that it was in Poland? Oh, because I think of the boomerangs

exclusively associated with Oceania. Yeah not, Yeah, they were. They were found in Native American tribes too, and stuff kind of all over the world. So Australian Aborigines use something called a kylie um exclusively for hunting at first, and they think, and this is I think the netst thing, because you certainly can't, you know, like find this out factually, but they think that eventually they stumbled upon one that kind of came back and they thought it was fun,

so they started throwing returning boomerangs. Yeah, because it's like just to get their kicks, just for kicks. Because returning boomerang you can't use for hunting well now, because if you if you throw returning boomerang, can hit an animal. If you hit the animal, it's not going to return back to you. That's that, it's not real. That same just cartoons everybody. So that's why there's two types. There's ones that you brain an animal with and there's another

that you just throw around to impress your friends. That's right. And apparently though the Aboriginal Australians figured out how to use returning boomerangs to hunt. They would put some nets up in trees. They would throw the boomerang, the returning boomerang, and then whoever was best at making like an eagle or hawks call would make that call and it'd scare all the birds because they'd see this thing flying here a hawks call, and they fly into the nets and

the Aborigines would eat them. Not a bad idea. So that's pretty much the history of boomerangs. Yeah, and they you know, no one owns a patent on the boomerang. There are many kinds of boomerangs that people have patented, of course, but the original boomerang was just hey, this was something we figured out on our own. It's like DNA, it belongs to the ages, it belongs to the universe.

So you're returning boomerang is going to be a little lighter obviously, because you're not trying to kill a rabbit. It's just for showing off. Yeah, and I've even you know, they have the little uh um nerf versions for kids. I had one of those when I was a kid, the little uh three pronged boomerang, and those are kind of fun. But if you look at videos of the real deal, like large three foot wooden boomerangs, it's pretty impressive to see. Like, you know, it's it's a tough

thing to do. You're not just going out there in your first try and have to fly back to you. There's actually like boomerang teams around the world. Yeah, us boomerang team. Unless you're a wonder kin of course or natural, I'm sure to do it you on your first time. I'm sure it's happened before. Maybe this maybe want to get a boomerang, By the way, did are you going to?

I don't know, maybe the boomerang team. What I'm hoping is a fan makes handcrafted boomerangs and since oh yeah, I hadn't thought about that, I'll bet we have at least one boomerang maker listener, So send us to Yeah nice, thanks Chuck. That way we can go out and perform a little two man boomerang. Maybe we can cross them and everything. So um the Again, the non returning boomerangs are pretty straightforward. It's the returning boomerangs that are lighter,

and they're they're made to be more aerodynamic. And the proper way to throw a returning boomerang is um to hold it at a vertical angle, to hold it up and down right, which is weird because if you ever see somebody throw a boomerang, when it comes back, it's horizontal. It's horizontally oriented. Yeah, it kind of just lands very softly like a helicopter. Right. The thing is is, it goes from upright to horizontal in the midst of this

path and it comes back to you. And if you stop and think about it like that makes zero sense whatsoever. A non returning boomerang certainly doesn't do either. Of those things. It's just the returning boomerang. And the whole reason behind this is because of the design of the returning boomerang.

It's basically a two pronged propeller that's not attached to anything that thanks to the force you give it and it's rotation and a whole other bunch of stuff that will get into it leans to the it falls to the left, turns clockwise, and comes back to you. That's if you're a right handed thrower with the right handed boomerang. If you're a left handed person, you have to have a left handed boomerang. It's a mirror image of the

right handed boomerang. If you try to throw a right handed boomerang with your left hand, it's not gonna work out. So well, I bet there's one person out there it's like, oh, I had no idea. So we're gonna muster up our courage and and get into the physics of the boomerang right after this. Alright, chuck, here we go. All right, So, I guess the first thing we should talk about is a little bit about just the physical design of the boomerang itself. The wings are slightly tilted, so it creates

what's called an airfoil, just like an airplane wing. Look out your plane window there and you're sitting on the wing. You're going to notice that the top of it is rounded and the bottom of it is flat, and that is going to give a plane lift and a boomerang lift. Right. The the air going over the top of the wing, because it's curved in like a tear drop shape. Um, it picks up speed right, so the air speed is increased,

which means the air pressure is also increased. Well beneath the wing it's flat, the air is just going through like it's whatever, but the air pressure is higher, so you have lower air pressure at the top, higher pressure at the bottom. That means that you have left that believe that it's Bernoulli's principle, is it? I think? So? Show off? No, not really so. So that's that's the whole thing behind both airplane wings, like you said, and

boomerang wings. Because again, if you if you really kind of want to start to understand boomerangs, um, first of all, do more research than just listening to this podcast. But secondly, you have to think of the boomerang is basically two airplane wings facing the opposite direction connected together. Okay, that's right, and that forms essentially a propeller. Yeah, and uh, a propeller is um. Well, it's it's basically, if you think about a boomerang, it has an axis, just like a

propeller does, but the axis isn't there. That makes sense, it's invisible. The propeller is connected to something because it has to lift the helicopter propeller cause that's the lift the helicopter, or if it's on the front of a plane, it's gonna pull that plane forward and up. Um, which is sort of a key we'll get to in a second. Um. But it's the same principle. But a boomerang just has

an invisible access let's say. Okay, so it does, and it's very important because at that axis, which you can just imagine is in the center of the boomerang where the two wings come together, that's the access of rotation that the boomerang has. It's spin. Yeah, and this article

does a good job of pointing out that. You would think, then if you just turned it completely horizontally like a frisbee, it would act like a helicopter propeller and just go up, yes, straight up, or if you turned it completely vertically, which is how you're supposed to throw it, it would just go side to side. But it doesn't do either one

of those things. No, and it doesn't. And the reason why is because if you turn on an air airplane propeller or a helicopter propeller rotor, it's it starts from a stationary position and just starts spinning, exactly the the boomerang doesn't start from a stationary position. It starts spinning along that central axis. And it's also thrown. Yeah, it's got that forward momentum already exactly. So it has now because you threw this thing. You threw it and it

started spinning around its own axis. But you also gave it that forward momentum, which is linear momentum, which means that it's now spinning around two axes. That's right, Okay, this is is this gyroscopic procession. We're close, we're almost there, and we get there chucked because of these two axes. So consider this. So the thing is just spinning around.

You've just thrown in. Its upright at a vertical it's vertically oriented to the earth, and you throw it, and when you throw it say it has a spin around that imaginary axis in the middle of the boomerang or at that point at like twenty kilometers an hour. Okay, because in Australia koter exactly well. Plus also I read a Japanese paper on this. That's what they use and

it makes sense. Um, And but you threw it that that that energy your arm transferred to it when you threw the frisbee to which gave it its linear momentum. Say that's making it move through space at a hundred kilometers per hour. Okay, that's right. So as the things spinning, whatever blade is at the top of the of the spin is going in the direction that you threw it, right, and you threw it at a hundred miles an hour,

and it's spinning at twenty kilometers an hour. That means that that top blade is spinning at a hundred and twenty kilometers an hour. You said miles. But yeah, we get it, Okay. I'm like, I'm just just barely hanging on here. The bottom one, though, is going in the opposite direction, so you're it's actually moving at twenty or eighty kilometers per hour. So the top is a hundred and twenty. The bottom one is working in the opposite direction,

so it's going eighty kilometers per hour. But these things are attached to the same thing, so this difference actually creates a difference in air pressure to its vertical orientation, which creates torque, which tilts it. Now we've entered gyros copic procession. Yeah, and I think I precession. I think I sort of said it like procession, but it's within e Yeah, it's like what gives Earth seasons. Yeah, that wobble.

The spin is another part of a very important part because when you throw it, and we'll get into exactly how to throw it here in a bit, but you want to give it a good wrist snap to give it as much spin as possible. Uh. And the spin is gonna be determined basically the rate of spin by a few things. The length to the wings, um, you know, if they're these huge wings, it's the spin isn't going to be as great, Uh, the angle that they're joined, and the amount of force applied by you the thrower.

And just like a gyroscope, which if we really wanted to torture ourselves, we should do one on gyroscopes. Man, that would be melt. My brain would melt. Yeah, I just my brain didn't process that stuff well. But um, like a gyroscope, it's gonna have more stability the faster it spin. So that's why you want that good risk snap. Yeah. And the reason why it has more stabilities because so that torque, that pressure that that's being created by that

difference in air pressure. Um, that forces being pushed down is actually stabilized throughout the spin of the boomerang. Right. Yeah. Like if you're going super fast on a bicycle and you take your hands off the handlebars, you're gonna keep going straight. If you're going like super slow, you're gonna

start wobbling around, right exactly. Um. The thing is is that pressure, that force of torque is constant, so it eventually because I think procession is if you're throwing with your right hand, procession always comes on in a counterclockwise motion. The torque turns, It turns the boomerang to the sides, which is why it eventually comes back around to you horizontally. That's what lays it down, and it also brings it in an arc that forms a circular path that comes

back to you. It's all gyroscopic precession. And it's because the boomerang, this little simple stick that's basically one crescent shaped piece of wood, turns into a gyroscope that that turns on three axis all at once. Yeah, all on one throw. And so it goes from straight it goes from stationary being straight up and down to spinning and curving around an arc back to you at a hundred kilometers an hour, all because you tossed it correctly. Yeah. And the the design, I mean, there are many, many

different designs of boomerangs. Um, Like I said, they can have two wings, three four, you can look like crawl and and have blades attached to them. Because there is something called a battle boomerang. Yeah, um man, that's that seems dangerous. Yea, it seems totally dangerous. I'll bet you can find that at like a head shop somewhere next to like a dragon pewter statue or something. You're probably the deal you can bind together for cheaper. Um. Some

of them do. Some of them have what's called turbulators though, which are can be a little bumps and pits on top which can increase the lift even more. And uh, I read an interview with one boomerang builder, and he was like, you can't. You know, I'm sure like NERF can with their their you know, soft ones, but like a true large three ft wooden boomerang, he said, you can't computerize these and build them like they kind of need to be handcrafted and thrown and then tweaked and

then thrown so you get it just right. And I saw um one of the U S Boomerang team guys demonstrating on video and he just put like a rubber band on his two I guess adjust it. So that makes sense, yeah, because you know, like if you're if you have a ceiling fan or something like that, you can add weights or something to stabilize it. That kind of thing. Yeah, Or when you get a when you get your tires and start installed in your car, you know, they put those little on those lead weights they to

uh what's it called align it? Yeah, to align it they put on that machine and if it's wobbling, they'll add the little weights. Yeah. I thought they thought there's a wizard in back. You're always in the waiting room drinking coffee and reading, browsing thelar making executer dragon statutes. No, it's kind of cool Actually, I think it's kind of cool.

It's really kind of nerdy to watch your tires get aligned, to put it on the machine and spin it, and it's really kind of just like this, and they look at it and if it's if it's wabbling at all, they know exactly where to tap on these little weights, because yeah, you don't want your tires to be the gyroscope, not at all. You don't. That makes for unsafe driving. Uh So I guess we should after this message break teach you how to throw a boomerang. All right, you've

got your boomerang. You're out in the field or on the beach. Beach is gonna be tough because wind is one of the forces that are going to act on that boomerang. There are five forces nervous force of gravity, the force caused by that propeller motion, the force of your throw, uh, force caused by uneven speed of the wing, and then the wind. And the guy that I watched throw on on YouTube um said that he liked to

throw on with a slight breeze in his face. And he said that that Um, it depends on the angle at which you're going to release it, though, depending on how the wind, and there's a lot of trial and air involved, and it's yeah, apparently you you want wind. I couldn't figure out what the deal is with this, but um it somehow helps the boomerang move. But you have what's called an angle of attack, and that's basically how you orient yourself to the wind. The winds blowing

in your face, you should turn and face. You don't want your shoulder now being hit by the wind, because that's ninety degrees. He turned a little bit to the right, so probably about like forty five degrees, and that's what you throw too, So you're throwing at an angle to the direction the wind is coming in. Yeah, but this guy kind of worked it out like he threw the um, you know, he kind of measured the wind. Uh, you know,

did the old finger test. Yeah, and he said, I'm gonna angle myself a little bit to the right and I'm gonna throw it. And he said, and it should land just in front of me. It went behind him. And he was like, well, I was wrong, so I didn't have a good wind measurement, so let me angle a little bit more, and sure enough, the thing came right back to him. Nice. So it all depends on what angle against the wind that you throw that thing, Bob say, Oh man, I can't stand that guy, really,

Bob Seeker. Yeah, I don't have anything against him, honestly. Yeah, that old time rock and roll song. I just turned that a song. That's his first piano keys. Yeah, I hate that song. Yeah, but overall I think Bob Seekers. Okay, he seems fine. He's a he's a working man. Yeah, yeah, turned the page baby. Oh yeah, I don't like that song either. I guess it's like against the wind, like a rock Oh. I hate that song, Hollywood Knights. That's a terrible song too. You hate Bob Seeker, No, but

I don't mind against the Wind. Surely there's other Bob Seekers songs outre Bob, get in touch with us and introduced me to your catalog. That would be great if he was a listener. Actually, he's just got a single tier doing on his cheeks. All right, So where were we we are? All right? You're gonna hold the boomerang with the V with the elbow pointing towards you and the V pointing out away from you, and again up

and down. It's vertically oriented. Yeah, vertically orient but at a slight tilt, like you don't want it completely straight up and down, but you're not throwing it like horizontally Like no, no, you're not gonna get very far that way. No. Actually it does go up and then comes back down in a loop. It basically does totally do something. Yeah, but interesting. Yeah, the thing is it's kind of dangerous, so you don't want to mess around with it. Yeah,

I mean we should point that out. These things are you know, heavy and made of wood and they come you know you're throwing it hard. Well yeah, I mean let's cut to the chase. Apparently when you throw a frisbee or a boomerang, which are virtually interchangeable in my mind, but they're really not not at all. Um, you want to keep your eye on it at all times, and if you ever lose sight of it, you don't look

around for it. You need to go take cover, cover your head and shout heads up and get everybody else to cover their heads too, because that thing can come back and collock somebody. Yeah, and that's if you haven't thrown it right. Like when I've seen the correct boomerang toss, it lands like a helicopter. Um, you know, straight up and down. So it's completely straight up and down. What what's the next step? All right, So you've got that v point pointing away from you, and you want putting

at you. No, no no, no, the two the you want the point facing towards you and the be facing away from you, and you want It's super important this part is you want that flat side. Remember we talked about the airfoil. You want the flat side facing out so to your right. If you're a right handed thrower, if you don't do that right then you're you're not gonna have a good result. Yeah, you would only probably tilt it to the left of the wind if you're left handed.

I would guess I don't know about that, Okay, I don't endorse that state. Okay. Um, So you're gonna hold it at the bottom of the wing, um like they say a pinch grip. The guy in the video called his a little pistol grip, like with two fingers and a thumb, and um, you want to snap your wrist when you throw it. And he didn't throw it super hard, like you don't have to really wing it. Yeah, he didn't. He didn't sound like stephie Graff when he threw it

or anything. Monica Sellis You mean I thought stephie Graft did that too? Was that Monica Sellis? There's a lot of grunters, but Monica Sellis she had it. That's who I meant. Then, but she got stabbed. Look what happened to her. Oh gosh, I thought that was stephie Graff too. Did you know stephie Graff and Andre Agasi are married? Yeah? Isn't that cute? It's adorable? Okay, you would be funny as if their kids were terrible at dinnis. They just

trip over their rackets whatever. Um, Bob seekers their coach, that's right, he's they're bad mitten coach. All right. So you you are snapping your wrist. You're throwing it basically like a baseball at a little slight angle, and you're gonna snap that wrist to give it the good spin. Um, you throw it vertically and hopefully it's gonna go out and up and curve around and then land back down fairly softly, somewhere close to where you are. And you don't want to try and catch it with your hand

like in a cartoon. Well you can, but you want to clap your hands together on yeah, yeah, like, don't try and catch it like a frisbee. No, but I think if you are a boomerang throwing person, you are trying to catch each one. Oh yeah, yeah, but you're a one hand and it's you clap it together, you trap it in between your two hands. Yeah. And if you're catching a frisbee like that, then God help you. Yeah, you're gonna get laughed at. But it's safe to It's

just you don't really have to be worried about it. Frisbee, it's super safe. Uh. I don't think I have anything else? Is that it? Well, just one other thing. Um. When I said that it's spinning around three axes. If were impressed with that, prepared to have your mind blown even more. It's spinning around three axes to lay down flat from the torque. It's also spinning around an additional three axes to follow that arc in a giant circle and come

back to you. So technically a boomerang when you throw it is spinning on six different axis from the point of release to the point of landing. Wow, you're not neat. It's pretty neat. Yeah, it's neat. And like this is one of those things where people were throwing these things long before we knew anything about how they actually worked. People figured them out, and then science came along afterward and said, oh, well, this is how it works, but

this stuff is so complex. Really kind of exposes that moment in science where you're like, I kind of have to have faith in this because I understand it so thinly that I just have to have faith that this is correct. And it's almost virtually the same thing as saying, well, the there's the gray wizard is the one who's moving it around in an invisible circle back to you because he wants you to prosper and not have to make a boomerang every time. Virtually the same thing at this

point in my understanding. Yeah, they're a great teaching tool as well. Um, I imagine if you're trying to teach physics in gyroscopic procession, then the problem is everybody, almost everybody I saw, except for the Japanese paper I think it was titled what makes a Boomerang come Back? Um, we're just terrible at explaining it. They understood everything, but they could not explain it in anything approaching Layman's terms. You know, I read a popular science article. Um, I

think it's called the Science of Boomerangs. That was pretty good. Wish you would have sent that to me because I've been agonizing over this for many, many, many, many many hours. I just figured you had your Japanese sources and we're good. It was in English too, well, of course it was, uh because gen Japanese. So good. Uh. If you want to know more about boomerangs, you can look up stuff all over the web. But why not star at our

website how Stuff works dot Com. It's type that word in the search bar and it will bring it up. And since I said search bar, it's time for listener mail. I'm just gonna call this I split Atoms for a Living, So you know we're on the wrong track already. Yeah, we're going to be corrected. Uh yeah, but he's very nice about it. I split Atoms for Living at a nuclear power plant. So I was really excited that you

did a podcast on nuclear science topic. Um. You guys really did a great job actually of breaking down a topic and making it accessible to a wide audience. Something I personally feel that organizations involved with new nuclear technology tend to struggle with a little bit Um anyway, I'm running in with a correction. You sayd that nuclear fission reactions involved the electromagnetic force, while nuclear fusion reactions involved

the strong nuclear force. I remember saying that both of these reactions actually get their energy from the same strong nuclear force. In both cases, if you were to measure the mass of the material before the reaction compared that to the material after the reaction, you would find that there's less because some of the strong nuclear force holding

the atoms together was released his energy. The difference in the energy release pretty much comes down to how much of this mass was converted divided by the mass of the atoms involved. Hey, let's see. The thing is is like that makes total and complete sense if you think about it. Sure that that makes it irritating that we got it wrong. Uh. Since adams um good for fusion are much lighter than adams good for fission, their reactions

are a bit stronger. Reactions which involve the release of stored electromagnetic energy are actually all of the reactions that involve electrons, which includes chemical reactions, Since this is a much weaker force. That's why there are such a huge energy difference between burning coal and nuclear energy. As you pointed out, the podcasts millions of times more potent. So

thanks again guys. Looking forward to the next one, and that is Jeffrey Hausiman from He's a reactor engineer in Zachary, Louisiana. Thank you very much. What's his name again, Jeffrey, Jeffrey. Appreciate that we love hearing from experts in the field. Uh. If you're an expert in your field and you want to correct us about something or whatever we want to hear from you, you can tweet to us at s y s K podcast and join us on Facebook dot com,

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